Справочник по конфигурациям в C# — 5.2. Поддерживаемые типы значений

{
  "Logging": {
    "LogLevel": {
      "Default": "Information",
      "Microsoft.AspNetCore": "Warning"
    }
  },
  "AllowedHosts": [ "example.com", "localhost" ],
  "FeatureFlags": {
    "EnableBeta": true,
    "MaxRetries": 5
  },
  "ConnectionStrings": {
    "Default": "Server=.;Database=MyDb;Trusted_Connection=true;"
  },
  "Kestrel": {
    "Endpoints": {
      "Http": {
        "Url": "http://localhost:5000"
      },
      "Https": {
        "Url": "https://localhost:5001",
        "Certificate": {
          "Path": "localhost.pfx",
          "Password": "dev"
        }
      }
    }
  }
}